The present invention relates to an oil resistant diaphragm having the liquid contact surface which is superior in resistance to deteriorated gasoline and low temperature. The diaphragm is suitable particularly for the fuel pump of the automobile fuel system.
The present-day automobile fuel system, especially the one equipped with an electronic fuel-injection system, needs a diaphragm that resists deteriorated gasoline resulting from the increased engine temperature and fuel pressure. The diaphragm should have the liquid contact surface which is resistant to the propagation of cracking caused by gasoline in contact at all times. In addition, the diaphragm has come to need low-temperature resistance with the spread of automobiles into cold districts. Heretofore, there has not been any diaphragm that meets all of such requirements.